Method of fluidizing material



July 23, 1968 c. SMITH 3,393,332

METHOD OF FLUIDIZING MATERIAL Original Filed Jan. 25, 1966 2 Sheets-Sheet 1 -FIG.|

FIG. 2

INVENTOR CARLOW EN SMITH BY M6 ATTORNEY C. SMITH July 23, 1968 METHOD OF FLUIDIZING MATERIAL 2 Sheets-Sheet 2 Original Filed Jan. 25, 1966 FIG.3

CARLOWEN SMITH BY M ATTORNEY FlG.6'

United States Patent M 3,393,832 9 METHOD OF FLUIDIZING MATERIAL Carlowen Smith, Irwin, Pa., assignor, by mesne assignments, to Industrial Pneumatic Systems, Inc., Fairmont, W. Va., a corporation of West Virginia Original application Jan. 25, 1966, Ser. No. 522,889, now Patent No. 3,356,264, dated Dec. 5, 1967. Divided and this application Sept. 22, 1967, Ser. No. 669,944

' Claims. (Cl. 222-1) ABSTRACT OF THE DISCLOSURE In a container for pulverulent material, a porous wall surrounds a discharge opening for supporting the material and a downwardly sloping surface supports the material beyond the porous wall. Air passes up through the porous wall to support and mix with the material adjacent the opening and a second current of air directed toward the opening is passed through a constricted outlet at the lower edge of said sloping surface, the reduced pressure at the outlet entraining the material above the outlet and carrying it with material above the porous wall to said discharge opening.

This application is a division of Ser. No. 522,889, filed Jan. 25, 1966, for Fluidizing Container and System, now Patent No. 3,356,264.

This invention relates to a system for fiuidizing and conveying pulverulent material by a current of air, and rockdusting mines with a system of this type.

A principal object of the invention is the construction of a container for delivering pulveru'lent material fluidized by entraining in a current of gas to provide the most efiicient use of the overall dimensions of the container, especially in height.

Another object of the invention is a container and vehicle carrier of low height for rockdusting in mines, with the maximum capacity for the dimensions which are adapted to mine operations.

Another object of the invention is the method of rockdusting by using a pneumatic container with a compressor carried on a vehicle in the mine.

FIGURE 1 shows a carrier with containers in accordance with the invention.

FIGURE 2 shows the cross section of a container of known shape.

FIGURE 3 shows a cross section of the container of the present invention.

FIGURES 4, 5 and 6 show a cross section of modified constructions.

Before this invention, containers for the conveyance of pulverulent materials entrained in air were made high with a small base to avoid the use of excessive volumes of air. As shown in FIGURE 2, the container 1 had a porous wall 2 spaced from the bottom wall 3 of the container to allow an air space for air admitted under pressure by inlet pipe 4. This porous wall 2 was pervious to air which passed into the material in the container and carried material entrained in it out through the outlet 5. The base and the air space were small so that the air would carry the material through the outlet pipe without loss of air. If the container were widened so that it would hold more material, the enlargement of the base and porous wall would require a much larger volume of air.

The improved system for rockdusting in mines embodies a plurality of pneumatic containers A according to the invention mounted on a vehicle carrier B. A compressor C furnishes air under pressure to the containers to convey the fluidized rockdust therein through the conduit D,

3,393,832 Patented July 23, 1968 which applies the dust in the mine. The low form of the container of this invention as shown provides for a large volume in the space available for entry into a mine.

By this invention, applicant can use a wide container and thereby convey a much larger volume of material in the same overall dimensions. The container 10 in FIGURE 3 has an end wall extending across substantially the entire width of the container with outlet at 12 in the wall. A bafiie 13 across the outlet and spaced from the end wall 11 provides a narrow passage or throat 14 for material carried by air out the outlet at 12.

The material within the container is supported on a porous wall 15 which forms a gas transmitting means spaced from the wall 11 to form an air space 16 to which air under pressure is admitted through inlet 17 from the compressor C. The porous wall 15, which is pervious to gas, extends from the outlet 12 toward the side wall, and the air or gas transmitted through the porous wall carries the material with it through the passage 14 to the outlet and out the conduit D.

The air which passes through the porous wall 15 is directed toward the outlet by baffles spaced from wall 15 as shown at 18 and 19. The battle 18 is also porous and is spaced from the outlet 12 and bafile 13, and extends over a major portion of the porous wall 15 adjacent the side wall of the container. Similarly, the second baffle 19 extends over only a portion of the bafiie 18 adjacent the side wall. As indicated by the arrows, these bafiies restrict the passage of the air into the material and direct a l ger portion toward the outlet. The currents of air thus resulting entrain the material and convey it through the passage 14 without waste of the air supplied to the space 16.

In a modified form of the invention as illustrated in FIGURE 4, a baflie of solid material, such as metal, is positioned at an inclination to the baffle 18 and extends to the wall of the container, forming a constricted passage between the bafiies. This baflle will direct the transverse current of air across the porous bafile 18 and to the passage 14, the reduced pressure of the gas in the passage carrying the pulverulent material with it.

In the form shown in FIGURE 5, a solid baflie 21 extends from adjacent the porous wall 15 to the container wall and directs air passing through the outer portion of wall 15 through the constricted passage between the bafiies and toward the outlet. As in the other forms, the air current at reduced pressure adjacent the passage will carry the material to the outlet.

In FIGURE 6, the porous wall supporting the material is formed with an inward portion 22 and an outward portion 23 which extends at an angle to portion 22 and into contact with the side wall of the container. A solid bafiie 24 is positioned parallel to and spaced from the wall portion 23, so that air passing through portion 23 is directed along the portion of the wall and into the material in both directions. The current directed toward the passage 14 will carry the material in the same manner as those in the other forms of the invention.

Containers of this form are especially advantageous in rockdusting of mines, where the vertical dimensions restrict the height of containers for use in this environment. As examples of containers designed for this operation, a container six feet in diameter with a height of only 31 inches has a capacity of 2500 pounds of dust, so that two containers, or two pods, can carry 5,000 pounds. An increase of only one inch in height will increase the capacity of one container by pounds. These containers are set between the side members of the vehicle carrier B as shown, so that the overall height of the unit is only five inches greater than the height of the containers.

The use of pneumatic containers of this low height mounted on a vehicle with a compressor provides an eflicient system of large capacity for dusting of mines, and avoids the difficulties and inefficiencies of the old hopper operation. These new containers may be quickly filled from storage containers, either outside the mine or through conduits to the inside. A large volume of material is furnished quickly and efiiciently for dusting within the mine.

The battle 13 across the outlet provides the passage 14 so that the transverse air current must pass along the porous wall 15 to carry out the material entrained in the air. Cooperating with this baffie, the 'bafiies spaced from the outlet direct currents of air passing through the porous wall toward the outlet and across the wall to assure the maximum entrainment of material. With materials of some types, the baffles 13 may be omitted and the other baflies controlling the air currents carrying the entrained material enable the use of containers of wide base and large volume for their vertical dimension.

While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and other changes in form and details may be made therein without departing from the spirit and scope of the invention.

What is claimed is:

1. The method of fiuidizing and discharging material in a container having a discharge opening comprising supporting one portion of said material above a gas transmitting means over an area adjacent said opening and supporting the remainder on an impervious support means beyond said area, passing a current of gas up through said material throughout said area and passing a second transverse current of gas toward said discharge opening through a reduced passage at the side of said area adjacent the impervious support means to create an area of low pressure at the side of said area and cause said material supported beyond said area to move into said second current to be carried with matenial in said area toward said discharge opening.

2. The method of fiuidizing and discharging material in a container having a discharge opening adjacent the bottom wall in which said material is supported above said bottom wall in an area adjacent said discharge opening and supported between said area and the sides of said container on an impervious, inclined surface sloping toward said area comprising passing a first current of gas up through said material throughout said area, and passing a second current of gas transverse to said first current toward said discharge opening through a constricted passage at the edges of said area and said inclined surface to form a region of low pressure to cause said material beyond said area supported on said inclined surface to move into said transverse current and mix with said material above said area while moving toward said discharge opening.

3. A method of fluidizing and discharging material in a container having a honizontally extending porous wall supporting said material on its upper surface and a discharge opening adjacent the upper surface of said porous wall, said container having inclined material supporting means extending from adjacent the sides of said container above said porous wall downwardly and horizontally toward said discharge opening and to adjacent said porous wall to leave a constricted passage between said supporting means and said wall, comprising passing gas upwardly through said porous wall to mix with the material above said porous wall, and passing gas toward said discharge opening through the passage between said inclined supporting means and porous wall, thereby producing a low pressure region adjacent said passage and drawing said material above said supporting means into the gas passing toward said discharge opening and further entraining the material above said porous surface in said gas passing over said porous Wall to and out of said discharge opening.

4. The method of fluidizing and discharging material from a container having a discharge opening in which the material is supported on a pervtious bottom wall to provide an air chamber between said pervious wall and the bottom wall of the container and on an inclined impervious wall sloping from the sides of said container toward the dis charge outlet and Wtlth its lower edge slightly spaced from said pervious wall to form a constricted passage, said inclined impervious wall being spaced from the bottom and sides of said container to provide an air chamber below said inclined wall, the step of supplying gas under pressure below said pervious wall to pass through said material above said pervious wall, and supplying gas under pressure to said space below said inclined wall to pass through said constricted passage across said pervious wall to said discharge opening and entrain material supported on said inclined wall due to the low pressure adjacent said constricted passage.

5. The method of rockdusting a mine comprising disposing rockdusting material in a container of greater transverse dimension than its height, said container having a discharge opening adjacent its bottom wall, supporting material on a gas transmitting support adjacent said opening and on an inclined, impervious support means beyond said opening, said inclined support means sloping toward said discharge opening and adjacent said gas transmitting support, passing a current of gas up through said gas transmitting support, passing a second current of gas transversely of said first current above said gas transmitting support through a constricted passage at the lower edge of said inclined support to provide a low pressure region to entrain material from above said inclined support in said second current of gas and convey it with material above said gas transmitting support to said discharge opening, and conveying said gas under pressure with said entrained material through a conduit and applying it for rockdusting in a mine.

References Cited UNITED STATES PATENTS 2,125,913 8/1938 Goebels. 3,188,144 6/1965 Gmur et al 222 X STANLEY H. TOLLBERG, Primary Examiner. 

